A significant typical weakness of sidewalls of pneumatic rubber tires is a relative lack of resistance to various puncturing objects. Such tire sidewalls, particularly for passenger tires, are composed of cord reinforced rubber plies of the tire carcass itself with a relatively thin visible outer rubber layer. Such sidewalls are particularly thin, as compared to the tire tread, in order promote their necessary relative flexibility and to reduce internally generated heat buildup as the tire is being run and its sidewalls subjected to a considerable dynamic flexing.
Accordingly, it is desired to provide a pneumatic rubber tire with a sidewall having a degree of resistance to being punctured with various foreign objects.
In the description of this invention, the term “phr” relates to parts by weight of an ingredient per 100 parts by weight of rubber, unless otherwise indicated.
The terms “rubber” and “elastomer” are used interchangeably unless otherwise indicated. The terms “vulcanized” and “cured” are used interchangeably unless otherwise indicated. The terms “compound” and “rubber composition” may be used interchangeably unless indicated. The term “carbon black” is used to refer to rubber reinforcing carbon blacks unless otherwise indicated. Exemplary rubber reinforcing carbon blacks may be referred to, for example, in The Vanderbilt Rubber Handbook (1987) on Pages 414 through 417.